Two-part rivet



B. P. COOPER TWO-PART RIVET Jan. 2, 1951 Filed Nov. 27, 1945 [n1/en for Basil P COO/oef I l I l l l l l l IL LQN Patented Jan. 2, 1951 UNITED STATES PATENT orties Basil Pomeroy Cooper, Leicester, England, assignor to United Shoe Machinery Corporation, .1. Flemington, N. J., a corporation of New Jersey Application November 27, 1945, Serial No. 631,039 In Great Britain December 14, 1944 The purpose of this invention is to provide improvements in two-part rivets of the type in which a pin having an upsetting head extends through a ductile sleeve member having an upsetting portion at one end and a head flange at the opposite end.

vThe pin, in a rivet of this category, serves initially to do the upsetting of the tail end of the sleeve member, but a portion of the pin is thereafter retained, if possible, in the installed sleeve member to reinforce its shear strength and, in some circumstances, to prevent the iiow of liquid fe. g. water) or gas (e. g. air) through the sleeve member. Accordingly, each pin is used but once, and, since the upsetting technique used to install such a rivet requires the stem of the pin to be considerably longer than the sleeve member, some portion of the stem projects from the head end of the sleeve member to be severed and discarded after the rivet has been installed.

The improvements provided by the present invention'are prompted by the problem of maintaining the two parts of a rivet in assembled relation both before and after the rivet is installed in a structure to he riveted. Prior to being installed, it is desired that the two parts shall be assembled in telescopic relation at the source where the rivets are made, and that this relation be maintained for the convenience of the op erator `of a riveting implement by which the rivet is to be installed.

The improvements hereinafter described provide for maintaining assembled relation of a pin cold forged trom wire Without being machined. and a sleeve member drawn from ductile sheet metal. 'Ihe stem of such a pin may be smooth and uniformly cylindrical, but a novel feature of the sleeve member is a barrel one portion of which is smaller than another portion and provided with a head flange larger than the larger barrel portion. The entire barrel may be initially a little larger than the stein of the pin and of uniform well-thickness, and the portion that is to be the smaller of the two may be squeezed by relatively movable die sections to reduce its internal diameter to a dimension slightly less than the size of the stem of the pin to be assembled therewith. When the stem is subseouently driven through the sleeve member tbe reduced portion of the latter will be slightly expanded by the stern and will have friction-tight engagement therewith. The tight relation thus obtained will not be lost in consequence of pulling the head of the pin into the larger portion of the barrel to install the rivet.

1 Claim. (Cl. 85-40) Referring to the drawing,

Fig. 1 represents a longitudinal section of the sleeve member of a rivet at the forming stage next prior to reducing the size of a portion of its barrel;

Fig. 2 represents a` similar view in which thel portion provided with a head flange is between a pair of squeezing dies and is reduced thereby to diameter smaller than the portion above it;

3 is a top plan View, on a smaller scale, of the contiguous portions of the squeezing dies ineluded in Fig. 2;

Fig. a is a sectional view that represents bothv members of a rivet as having been assembled,

i and as having been placed, but not finally inis slightly smaller than the throat of the barrel.v

because the punch used to make it cannot be quite as large as the throat Without causing trouble in the punching operation. Consequently, an upsetting pin capable of sliding through the hole 5 will be too small to be gripped by any other portion of the sleeve member. Therefore, to prepare the sleeve member :for the reception of an upsetting pin, a band 'l of the barrel 3 is squeezed or contracted as represented in Figs. 2 and 4.

The band 'l adjoins the head flange I, but before it is squeezed the sleeve member is placed on a cylindrical patriX i3 no larger than the hole 5, and preferably a little smaller. The squeezing may be done by a pair of cooperative die members il, 9 (Figs. 2 and 3) movable toward each other. The upper portions of these die members have semicylindrical mated cavities that provide clearance for the sleeve member, but the lower portions have diametrically opposite operating formations il. ll that do the squeezing. Viewed as in Fig. 3 the formations Il, Il are crescent-shaped, and they press opposite segments of the band 1 toward each other as far as the patrix i3 will permit. One such squeezing operation will produce an oval cross section of the deformed band of the barrel, but the minor diameter of this band will then be no larger than the hole 5. If a circular cross section of the deformed band is desired, it may be obtained by separating the die members, relatively turning them and the sleeve member 90 about the axis of the latter, and repeating the squeezing operation.

Fig. 4 includes `an upsetting lpin comprising a head l5 and a smooth cylindrical stem l1 longer than the sleeve and of uniform diameter. Pins of this type may be made by cold forging wire stock, preferably a little larger than the smallest inside diameter of the contracted band 1 of the sleeve member. The band l will maintain friction-tight engagement with lthe stem 'H of a pin assembled with the sleeve member intelescopic relation, and if the two members are so assembled at the source Where the rivets are made they will remain so despite normal handling. Consequently, when the operator of a rivet-installing implement takes up a rivet his duties Will be simplied accordingly.

In'FigA the rivet assemblage has been placed ina hole in .a structure to be riveted, that structure being represented as comprising two layers i9 and 2i having an aggregate thickness alittle greater than 4the :length kof the friction-tight band l of the .sleeve member. Since the hole in which the 'sleeve Vmember Vis placed must be as large as the `larger yof the two barrel portions it will provide two segmental 'spaces 23, 23 or one annular `space surrounding the smaller barrel portion. .At the same time, the throat of the larger barrel'portion will lprovic'ie an annular space v2li surrounding a portion vof the stem I1.

if, now., the rivet be installedwith .an implement comprising an anvil for bracing the flange l, and means for pulling ythe stem il (e. g. vsee U.'S. Patent No. 1,829;696,"Wylie et al., October 27, 1931), the head l5 will be drawn toward the angebut before `it can enter the sleeve member i' it willoompress the latter endwise, thereby lpacking rivetmetal into the space 'or spaces 23 and into the space 25within the confines ofthe layer i9. Finally,v the 'unconned portion A`of the barrel,

unable to withstand the maximum compressive force, lwill yield radially away 'from )the `stern l1 and the head i5 `will venter r`it, 'with the result villustratedrin Fig. 5.

The projecting portion of the stem I1 may be cut off adjacent to the fiange I to leave a plugv 21 in the sleeve member. The friction-tight barrel portion of the sleeve member will continue4 to grip this plug regardless of failure of the tail end of the sleeve member to close in over the head I5 as illustrated. An alternative expedient, preferred by some to do away with cutting oil the stem l1, may be provided by forming an annular groove 29 (broken lines in Fig. 4) in the stem. The stem will break at this point, provided "the projecting portion thereof is pulled with sum- 'cient yforce after the upsetting operation has been accomplished. This practice will leave a plug 31 (Fig. 5) in the 'friction-tight portion of the l "sleeve member.

.Having ydescribed my invention, What I claim as new and desire to secure by Letters Patent of the United States is:

A two-part rivet comprising a sleeve member.

REFERENCES `CITED The following references are lof record 'in the iile of this patent:

UNITED STATES APATIEIN'JTS Great Britain May I7, '191W 

